For the adjustment of a camshaft, the prior art discloses inter alia electromechanical camshaft adjustment systems. In electromechanical camshaft adjustment systems, use is usually made of three-shaft gearings in which a first shaft of the gearing, usually the drive input shaft, is connected to the camshaft sprocket of an internal combustion engine, a second shaft (drive output shaft) is operatively connected in terms of drive to the camshaft via the camshaft sprocket, and a third shaft, the adjusting shaft, is connected to the rotor shaft of an electric adjusting motor (electric motor). The adjusting shaft serves for adjusting the relative angular position between the camshaft and crankshaft during operation of the internal combustion engine. Examples of such three-shaft gearings are swashplate gearings and internal eccentric gearings, which are described in WO 2006/018080. Said three-shaft gearings also include the shaft gearing known from WO 2005/080757 and the gearings in US 2007/0051332 A1 and US 2003/0226534 A1.
As actuators in such three-shaft systems, electric motors are often used for adjusting the adjusting shaft. It is however likewise possible to use electrical, mechanical or hydraulic brakes or rotationally or linearly acting electromagnets to permit the phase adjustment.
All of the known camshaft adjuster systems are designed, in terms of their operating principle and/or their dimensions, for the phase adjustment of the camshaft during engine operation. With such systems, it is not possible for the actuator and actuating element to also be used for pre-positioning the crankshaft when the engine is at a standstill.